Well thanks for the compliment, though I personally am not totally happy with the guitar tone on the first album. I think I'm getting much better tones nowadays...
Anyway, it ALL starts in the amp. Which version of the POD do you have? I know the POD XT can get some really good tones, though I don't have experience with the other models. To me though, nothing quite captures that sound like the real thing: a nice tube amp through a 4x12. The amp settings are really 95% of the battle in my opinion. Obviously mic selection and placement are very important as well, but if you have the sound right at the source, it's pretty easy to capture if you know what you're doing.
It would be hard for me to make any real recommendations without hearing the tone, but from what you describe, my first two suspects would be the bass knob and the gain knob. On a lot of amps (Mesas are notorious for this), the tone controls strongly influence each other, so if you don't have the bass set right, for instance, the treble will also kinda be out of whack. A lot of times the instinct is to turn the bass way up because you're going for that thick low-end crunch, but it's also easy to muddy it up this way before you know it.
The same goes for gain. Live, you can get away with ridiculous gain, but you'll probably have to back it off a bit for recording. Now, within reason of course. Some people act like you have to dial in some early-70s sounding wimpy tone for recording, and that is by no means the case. Make sure it has balls and sustain. However, you'll find that adding gain past a certain point really doesn't add anything to your tone, and actually starts taking away from it because it makes things cloudy and you start to lose definition. It's kinda subtle at first, but you might find that backing off the gain a little bit clears up your midrange.
Then again, if it's just flabby with no power, it might be a different problem completely and you might need more gain to tighten it up. Like I said, it's hard to know what the tone needs without hearing it.
As for processing, definitely keep your rhythm tracks dry. No reverb, no chorus IMO if you want that nice, in-your-face sound and aren't going for a special effect. Some people like a slight delay behind the rhythm tracks to make them sound thicker, but be careful if you do that because weird things can happen with phase, and the sound might be all out of whack when you listen in mono instead of stereo.
Leads are a different story. A touch of delay and reverb really makes a lead sound nice and alive IMO; I can't stand the way they sound without it. I also use chorus and reverb for clean sounds.
No other processing for guitars here. To me there's generally no need to compress electric guitar tracks, because they're already so compressed that they're almost a square wave. However, I might compress just the low mids with a bandwidth compressor if I find the recorded tone is sounding too muddy and/or fighting with the bass down in that frequency range. You might need to compress a solo if the dynamics are too extreme, but not very much.
There are NO RULES! Just whatever sounds good and whatever it needs.
Anyway, I hope that helps a little bit at least.
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